I've not done much cooking with pearl barley, so it always comes as a surprise just how much it expands! And it's sooooo filling too. I realised a little late in the day that if I made the recipe as written, we'd still be eating this come next Christmas! So after a hasty re-think I made a less-barley-more-bake version; in other words, I used the same amount of onion, tomatoes and mushrooms and halved everything else! I must admit I hankered after a bit of cheese, but resisted; I was also tempted to add some Marmite, but I left well alone. This meant that we were able to appreciate the finely tuned combination of flavours from the sweet potato, tomatoes and herbs.